GENETICS

The Rules of Inheritance

1866 CE

Phanerozoic · Cenozoic · Quaternary · Holocene · Meghalayan

Counting pea plants for eight years, a monk in Brno found that inheritance does not blend. Traits come in discrete units that separate when gametes form and recombine in the next generation, which is why a trait can vanish in one generation and return whole in the following one. He published in 1866. The paper was cited four times in the next thirty-four years.

Why it matters

Darwin's argument needed exactly this and did not have it. If inheritance blended, every new variation would be diluted by half in each generation and natural selection would have nothing to work on. The answer was in print seven years after the Origin of Species, and nobody who needed it read it.

Dating & uncertainty

The experiments ran from 1856 to 1863 and the paper appeared in 1866. It was cited four times in the following thirty-four years, and only after 1900 did anyone see what it meant.

Sources

1. Nasmyth (2022), Nature Reviews Genetics · The magic and meaning of Mendel's miracle
2. van Dijk et al. (2022), Nature Genetics · How did Mendel arrive at his discoveries?
3. Charlesworth & Jones (2022), Nature Genetics · From Mendel to quantitative genetics in the genome era

Earth history as one day

23:59:59.99703.0 ms before midnight

if Earth’s 4.54 billion years were compressed into a single day